The role of GTD in optimizing biorthogonal filter banks

Filter bank optimization for specific input statistics has been of great interest in both theory and practice in many signal processing applications. In this paper we consider biorthogonal GTD (generalized triangular decomposition) filter banks for optimizing the coding gain. We develop some theoretical results for the optimal biorthogonal GTD subband coder. We also show in both theory and numerical simulations that biorthogonal GTD subband coders have superior performance than biorthogonal subband coders, orthonormal GTD subband coders, and orthonormal subband coders. In addition, the uniform bit loading scheme can with no loss of optimality be used in the optimal biorthogonal GTD coders, which does not have the granularity problem arising in the conventional optimum bit loading formula.